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Publication numberUS4859423 A
Publication typeGrant
Application numberUS 07/130,397
Publication dateAug 22, 1989
Filing dateDec 9, 1987
Priority dateDec 9, 1987
Fee statusLapsed
Publication number07130397, 130397, US 4859423 A, US 4859423A, US-A-4859423, US4859423 A, US4859423A
InventorsDaniel Perlman
Original AssigneeBrandeis University
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Plastic pipette canister
US 4859423 A
A pipette canister formed from a thermoplastic material. The canister withstands dry heat above 160° C. reduces breakage of glass pipettes stored within, and the material is free from metal oxide residues.
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I claim:
1. A pipette canister comprising an elongated tube having a longitudinal axis along a length of said tube, said axis having an internal length greater than the length of a pipette, and having a diameter sufficient to allow storage of a plurality of pipettes, said tube having a closed base and an open top end wherein said canister is formed from a thermoplastic material consisting essentially of polyetherimide, said canister can withstand steam heat above 120° C., and dry heat above 160° C., said material is free from metal oxide residues, and wherein glass pipettes are protected from impact-breakage with said canister by the use of said thermoplastic material.
2. The pipette canister of claim 1 wherein said material is optically transparent.
3. The pipette canister of claim 1, having a wall thickness of 1/16" or more.
4. The pipette canister of claim 1, wherein said material is extruded as a cylindrical or rectangular cross-section.
5. The pipette canister of claim 1, having the closed base formed at an acute angle to the longitudinal axis of said canister, wherein said base causes pipettes inserted into said canister and in contact with said base to be offset from one another, each pipette having a mouthpiece, wherein each mouthpiece can be separately grasped, thereby enabling removal of a pipette canister without touching a mouthpiece of other pipettes.
6. The pipette canister of claim 1, said canister having a known diameter and having means defining an aperture near said top end, said aperture being narrower than the diameter of said canister along the length of said canister, wherein an individual pipette can pass through said aperture and be delivered to a user in a sterile condition.

This invention relates to canisters suitable for holding glass pipettes for sterilization.

Glass pipettes are commonly used for accurately measuring and dispensing volumes of fluids. For some uses it is important to dispense such fluids in a sterile manner and thus the pipettes are sterilized either by dry heat at 160°-180° C. or by steam heat at 121° C. in an autoclave. During sterilization, and subsequent storage, groups of pipettes are held within a cylindrical or rectangular box-shaped canister having a lid. These canisters are commonly formed from stainless steel or aluminum, and are provided with a wad of cotton or glass wool to cushion the fragile tips of pipettes, which otherwise break upon impact with the bottom of the canister during loading or transport of the canisters.

Harker, U.S. Pat. No. 3,474,929, describes an open wire container having a plastic bag containing disinfectant. The bag is autoclaved when filled with pipettes. After use this bag is thrown away.

Erickson, U.S. Pat. No. 4,436,700, describes a stainless steel canister having a flat disc-shaped bottom, suitable for autoclaving of pipettes.


The invention features a canister for housing and sterilizing glass pipettes. The canister is formed from a thermoplastic material. The canister withstands steam heat above 120° C. and dry heat above 160° C., and the thermoplastic material is chemically inert and free of contaminating metal oxide residues. Further, the plastic reduces the possibility of breakage of glass pipettes upon impact with the canister.

In preferred embodiments, the material is optically transparent, has a thickness of 1/16" or more, and is polyetherimide, polysulfone, or other suitable heat-stable thermoplastic extruded as a cylinder or rectangular canister. The pipette canister has a base formed at an acute angle to the longitudinal axis of the canister, wherein the base causes pipettes inserted into the canister and in contact with the base to be offset from one another, and wherein any one pipette can be removed from the canister without the hand of a person removing the pipette touching other pipettes; the pipette canister has an aperture near its top end, the aperture being narrower than the internal diameter along the length of the canister, wherein an individual pipette can pass through the aperture and be delivered to a user in a sterile condition.

This invention provides a pipette canister which allows sterilization of glass pipettes without compromising their chemical cleanliness or physical integrity. Unlike metal canisters, the present thermoplastic canister avoids transfer of metal ions or metal compounds to the pipettes during sterilization or storage. Thus the sterile pipettes are suitable for use in experiments in which trace metal elements or metal oxides affect the outcome of the experiment. A highly desirable feature and advantage over metal canisters is the breakage protection afforded glass pipettes housed in plastic canisters. This protection appears to derive from both the flexibility and relative softness of the plastic surfaces compared to metal surfaces. Further, since the canister is transparent, and remains so even after several uses, visual inspection of the inner portion of the canister is possible and any visible residues remaining after use can be readily removed. Thus, these residues are not transferred in future use to other pipettes. This transparency also provides visual inspection of the type, size, number, and integrity of pipettes within a canister. In addition, the canister can be formed with a flexible plastic base, suitable for causing each pipette in the canister to be offset from each other with their mouthpieces fanned out at different distances from the lip of the canister. Thus, a single pipette can be removed from the canister without affecting the sterility of other pipettes. Similarly, a funnel-shaped exit port can be formed at the open end of the canister and allow pipettes to be individually delivered from the canister. Flexibility of the various plastic surfaces inside the canister eliminates the need for cushions e.g., glass wool, in protecting the ends of pipettes from breakage. Solid glass, if used to fabricate such a pipette canister, would confer some of the above advantages over metal, but would create a fragile container, itself susceptible to breakage, and contribute to breakage of the pipettes within.

Other features and advantages of the invention will be apparent from the following description of the preferred embodiments, and from the claims.


The Figures will first be briefly described. Drawings

FIG. 1 is a perspective view of a canister and its cap;

FIG. 2 is a longitudinal sectional view of a canister having a slanted base; and

FIG. 3 is a longitudinal sectional view of a canister having a funnel shaped exit port.


Referring to FIG. 1, canister 10 is generally an elongated cylinder formed of extruded polyetherimide (Ultem™, manufactured by General Electric). Canister 10 has a circular base 12, an open end 14 and a wall thickness about 1/16". Also provided is a cap 16, which is a cylinder having a base 18 and an opening 20, sized to slide over the open end 14 of canister 10.

Referring to FIG. 2, in one embodiment canister 10 is provided with a removable sloping plastic surface 22 at its base. Surface 22 acts to cause pipettes 24 within canister 10 to fan out so that each mouthpiece 26 is separated and separably accessible to a hand 28 of a person. Surface 22 is also formed from polyetherimide and is inclined at an angle of about 30° to base 12.

Referring to FIG. 3, in another embodiment canister 10 is provided with a removable funnel shaped exit port 30 formed of polyetherimide. Port 30 has an opening 32, wide enough to allow passage of at least one pipette 24.


Canister 10 is used in a standard way by inserting pipettes 24 to be sterilized within the canister inserting port 30 when required and placing lid 16 over opening 14 and placing canister 10 within an oven or within an autoclave. It is preferred that sterilization is by dry heat since steam borne aerosol material in an autoclave may cause chemical contamination of the pipettes.

Other embodiments are within the following claims.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2614027 *Apr 28, 1948Oct 14, 1952Kollsman PaulDevice for sterilizing hollow thermoplastic articles by heat
US3474929 *Jun 26, 1967Oct 28, 1969Bellco Glass IncDecontamination unit
US4046254 *Sep 19, 1973Sep 6, 1977Kramer Steven GSurgical trays
US4191291 *Jan 25, 1979Mar 4, 1980Brown Ronald WDental organizer and container
US4349118 *Apr 28, 1980Sep 14, 1982Roger S. SandersonSterilizing and storing medical items
US4436700 *Jan 4, 1982Mar 13, 1984The Board Of Regents Of The University Of NebraskaSterilization
US4466552 *Aug 8, 1983Aug 21, 1984American Hospital Supply CorporationSterilization container formed of nonwoven material
US4541992 *Aug 10, 1983Sep 17, 1985Hu-Friedy Manufacturing Co.Apparatus for organizing, sterilizing, and maintaining medical/dental instruments
US4643303 *Oct 15, 1985Feb 17, 1987Micromedics, Inc.Modular sterilizing system
US4661326 *Feb 25, 1985Apr 28, 1987Herbert SchainholzSterilization container
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5340550 *Nov 2, 1992Aug 23, 1994Jordco, Inc.Interengageable, overlapping, hollow cap and base portion are fitted together forms a cavity and fluid passage for continuous fluid flow
US5533618 *Oct 11, 1994Jul 9, 1996Pickels, Jr.; Robert F.Surgical holster
US5681539 *May 28, 1996Oct 28, 1997Riley Medical, Inc.Separated fingers extending from base
US5827487 *Feb 26, 1997Oct 27, 1998Riley Medical, Inc.Medical instrument fixation method and means
US5858304 *Jan 14, 1997Jan 12, 1999Steris CorporationVacuum jacketed steam sterilizer
US5915583 *May 21, 1997Jun 29, 1999Abbott LaboratiesFor holding a patient sample
US7624868 *Nov 21, 2006Dec 1, 2009Cook Vascular IncorporatedPipette holder
US7703977Mar 23, 2007Apr 27, 2010Anna KnishevitskiyAseptic thermometer storage case
US8231734Jan 23, 2003Jul 31, 2012Jordco, Inc.Porous material for insertion cleaning of instruments
US8635735Jul 30, 2012Jan 28, 2014Jordco, Inc.Porous material for insertion cleaning of instruments
U.S. Classification422/564, D24/224, 206/586, 422/310, 422/297, 206/443, 422/300, D09/504, 206/419, 436/1, 422/307, 206/524.6, 206/524.1, 206/305, 206/214
International ClassificationB01L99/00, B65D85/30, A61L2/26
Cooperative ClassificationA61L2/26, B65D85/30, B01L99/00
European ClassificationA61L2/26, B65D85/30, B01L99/00
Legal Events
Nov 9, 1993FPExpired due to failure to pay maintenance fee
Effective date: 19930822
Aug 22, 1993LAPSLapse for failure to pay maintenance fees
Mar 23, 1993REMIMaintenance fee reminder mailed
Dec 9, 1987ASAssignment
Effective date: 19871203